1. Field of the Invention
This invention relates generally to busses for memory cards to allow a Digital Signal Processor (DSP) on a memory DIMM or SIMM to communicate with a system memory controller, and more particularly to the use of a serial bus for communication of a DSP on a memory card with a system memory controller.
2. Background Information
The use of DSPs on memory cards is now being proposed as a way for providing a relatively inexpensive processor on a memory card which can perform tasks on the card while the system bus is otherwise occupied. This works well in so far as it goes; i.e. as long as the DSP needs to be used only on the card on which it resides and does not need to communicate with the system bus this arrangement is fine. However with the present proposals there is no mechanism for the DSP on the card to initiate communication with the system bus and ultimately with devices controlled by the system bus. Since the DSP is a relative powerful processor it is desired that a technique be provided for a DSP to initiate communication effectively and simply with the system bus.